Color-stabilized mineral oil



Patented Sept. H, 1934 written stares tenn s rarest eerie @(BLGR-STABIHLEZED MTHNERAL GEL Wander-veer- Vool'hees, Hammond, End, assignor to Standard Gil Company, Chicago, llllL, a corporation of Indiana No Drawing. Application December 21, 1931, Serial No. 582,496

14. Claims.

become discolored during storage and use, evenat low temperatures. When motor oils are used in internal combustion engines or when used under oxidizing conditions they deteriorate in color and appearance and such deterioration is 19 usually accompanied by a more or less impairment of the oil in other respects, such as the formation of sludge. Transformer oils form sludge after being in use for relatively short periods of time and consequently are impaired in their insulating properties. Also it is well known that turbine oils have a tendency to emulsify and deteriorate in color.

I have found that the deterioration of the above mentioned oils can be retarded to a remarkable 2 extent by adding to the mineral oil a small amount or" a stabilizing agent of the class or alkylenediamines of the following general formula:

wherein R and R1 represent either hydrogen atoms, alkyl radicals, aryl radicals, or derivatives thereof. Also, I may use compounds prepared by substituting one or more of the hydrogen atoms attached to the carbon atoms in the above formula with the following radicals or their equivalents: CH3, CzHs, Cal-I1, C4H9, CHaCI-IaCI-izCH-zCHz,

051111, 06115, osnicrn, C6H5CH2, CHZCHZNHQ,

CGHQNHZ, CsH4OH, CIOH'I. The hydrogen atoms on the amino group may be substituted with one of the following radicals or their equivalents; CH3, C2H5-, C3H7-, C4H9-, CH3CH2CH2CH2CH2, C5H11, CH2CH2NH2, 01 a group having the formula Table I SampIe -Winlder lubricating oil-8595 Saybolt -viscosity at 210 F.

Temperature of tests 180 F. Iron wire in each sample initial true color of sample 28 True color units of i Parent 0 1 afteri I Stabilizer dd d 46 days 83 days 9999999 0 -E8SE38 b3 mwcewaxmq unts-4, 00

From the above table it is readily seen that the allrylenediamlnes stabilize the lubricating oils and greatly reduce the formation of color. I have found that the extent of color stabilization produced by the alirylenediarnines also gives a good indication of the extent to which the alkylenediamines prevent sludge formation, and prevent the oil from deteriorating in other respects.

The following table shows the stabilizing'eilect of the alkylenediamines on lubricating oil with a higher viscosity and deeper color than the oil used in the above example:

Table II 9o Sample-Winkler lubricating oi1110 to 125 Saybolt viscosity at 210 F.

True color units 0! oil alter- Percent Stabilizer added 83 days Propylenedlamine. Propylenediamine 8888 CHM All examination of the above tables will show that the alkylenediamines having the higher molecular weight are more effective than the alkylenediamines of lower molecular. weight. This increase in effectiveness will in general be observed also with other alkylenediamines of higher molecular weight than prophylenediamine. The true color scale proved to be a-very convenient scale for noting the extent of stabilization produced by the polyamines. A comparative study of the true color scale was published in the Industrial and Engineering Chemistry for 1926, Vol. 18, page 164.

For the purpose of my invention, any of the alkylenediamines of the above general formula may be used in mineral oils to prevent deterioration of oils, for example, 1-2 diamino ethane, 1-2 diamino Z-methyl ethane, 1-2 diamino 2 butyl ethane, l-2 diamino 2-ethyl ethane, l-2

diamino l-2 dimethyl ethane, v1-2 di(propyl amino)ethane, l-2 di butyl amino) ethane, l-2 (diethyl amino) ethane, and the like.

The above inhibitors may be used in different concentrations, but preferably not over 0.1%. Satisfactory results are nearly always obtained when concentrations within the range of 0.02 to 0.005% are used.

It will be observed that an iron wire was used in each of the samples tested for the purpose of simulating the conditions when the oils are used in metallic containers.

The alkylenediamines hereinabove described, can be prepared by the interaction of ammonia or amines and an oleflne, such as ethylene or propylene. Also they may be prepared by the interaction of ammonia or amines and a dihalogenated oleflne, such as ethylene dichloride or propylene dichloride. Suitable amines are propylamine, butylamine, diethylamine, ethylaniline and their homologues and isologues. The alkylenediamines prepared by these methods contain appreciable amounts of high molecular weight polyamines resulting from the condensation of two or more molecules of the alkylenediamines through the amino groups. In practicing my invention it is not necessary to remove the condensed and polyamines from the simple allwlenediamines. In fact these condensation products are very good stabilizers in themselves. The above mentioned condensation products may have cyclic formulae of the type NH (CnH n) NH or N E (CnHm); E N.

Examples of such products are diethylene-diamine, triethylenediamine, dipropylenediamine, trlpropylenediamlne.

The following equation represents the probable course of the reaction when ammonia is treated with a dihalogenated oleflne.

C2H4B1'2+2NH3=H2N-C2H4NH2.2HB1. The following equations account for the presence of the cyclic condensed amines:

' UHF-CH:

2o,H.Bn+4NH==HN NH.2HBr+2NH4Br.

CH -CH! CHI-CHI Also condensation products containing the following polyamine nucleus may be formed by the above reactions:

wherein R1, R2, and R3 may be either a hydrogen atom, alkyl, or H2NCH2-'-CH: group.

To liberate the amines from their salts, the mixture is distilled with potassium hydroxide or other alkalies and the amines are distilled over. The distillate comprises a mixture of ethylenediamine and condensation products of which the above equations show examples.

It is apparent that the compounds that I have found to be suitable are 1-2 diamino ethane and derivatives thereof. Also I have found that the 1-2 diamino ethane compounds of high molecular weight are somewhat more effective than those of low molecular weight.

Although the present invention has been described in connection with the details of specific examples of oils, it is not intended that such examples shall be regarded as limitations upon the scope of the herein described invention.

I claim:

1. A viscous lubricating oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of an aliphatic amine having the following general formula:

wherein the hydrogen atoms attached to the carbon atoms may be substituted with an alkyl radical, and the hydrogen atoms attached to the nitrogen'atoms may be substituted with an alkyl radical.

2. A viscous mineral oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of a dialkyl substituted 1-2 diamino ethane.

3. A viscous mineral lubricating oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of 1-2 diamino ethane .wherein at least one amino hydrogen has been replaced by an alkyl group.

4. A viscous mineral lubricating oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, less than 0.1% of an aliphatic alkylene polyamine.

5. A viscous mineral oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, less than 0.1% of a mixture of aliphatic alwlene polyamines.

6. A viscous petroleum hydrocarbon distillate normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of the aliphatic polyamines prepared by reacting dihalogen aliphatic hydrocarbons with ammonia.

'7. A viscous mineral lubricating oil normally unstable with respect to color formation on storage and containing, as a color formation inamine.

8. A viscous mineral oil normally unstable with respect to color formation on storage and containing, as a color'formation' inhibitor, a small proportion of ethylene diamine.

. hibitor, a small proportion of a propylene poly- 9. A viscous mineral lubricating oil normally v unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of an aliphatic amine prepared byrreacting 1-2-dlchloro ethane with ammonia.

10. A viscous mineral oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of an aliphatic amine of the following general formula:

wherein R represents an alkyl group.

12. A viscous mineral oil normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of an aliphatic amine having the following general formula:

wherein the hydrogen atoms attached to the nitrogen atoms may be substituted with an alkyl radical selected from the group consisting of CH:, C2H5-, CaH7-, C4He-, CH2(CH2) 4- CsHn, NH2CH2CH2-, radicals.

13. A viscous mineral lubricating oil normally unstable with respect to color formation on storage and containing as a color formation inhibitor,

4;. small proportion of an aliphatic amine having the following general formula:

H H H,N J o-Nm wherein any of the hydrogen atoms attached to the nitrogen atoms, may be replaced with alkyl groups.

14. A viscous petroleum hydrocarbon distillate normally unstable with respect to color formation on storage and containing, as a color formation inhibitor, a small proportion of a propylene polyamine.

- VANDERVEER VOORHEES. 

